Ligation is the medical act of restricting blood flow in a blood vessel or other tissue. Traditionally, tissue ligation is conducted using a ligature usually in the form of a suture thread or string, tied around the tissue. Other prior art ligation devices include metal or polymer clips that are pinched around the tissue.
Even though the ligature is a very simple device, the act of tissue ligation can be cumbersome, sometimes requiring the operation of more than one medical person. For instance, in some surgical operations the tissue to become ligated needs to be lifted slightly from surrounding tissue in a subject. However, tying the ligature thread around the lifted tissue typically requires two hands, in particular when tightening the thread around the tissue and locking the thread with a knot. In these cases, the tissue has to be lifted, potentially by another medical person, from the surroundings or the surrounding tissue has to be withdrawn.
There is therefore a need for a medical device that has the potential of being used for tissue ligation and can be operated with one hand. The design of a cable tie's self-locking loop offers such an opportunity.
US 2005/0288674 discloses a bio-absorbable bone tie having a convex locking case and an elongated band used for securing fragments of a fractured bone together. The bone tie is basically constructed as a traditional cable tie with the exception of the convex locking case.
U.S. Pat. No. 4,001,898 discloses a self-locking cable tie with a head carrying a non-pivotal locking means extending into an aperture through the head and securely engaging a selected abutment of a strap of the cable tie. Pusher means is carried by the head and extends into the aperture. The pusher means is responsive to retrograde movement of the strap to push the abutment to be held into engagement with the locking means.
WO 2009/091313 discloses a medical device comprising an elongated, flexible band equipped with ratchet members and connected to a device head having a channel dimensioned for reception of the band. A lock member is connected to the device head and configured to interlock the ratchet members when the band is pulled through the channel to form a reverse-motion brake. A protrusion and a matching protrusion receiving member are arranged in the device head in connection with the channel entrance and in the band in connection with the band-locking case interface. The protrusion receiving member is dimensioned for reception of the protrusion when the band is close to fully pushed into the device head.